With the development of technology, more and more electronic devices, such as smart phones, tablet computers, laptops and smart televisions and so on, appear in people's lives. There devices greatly facilitate people's lives.
Currently, contents may be displayed by using a projection in many situations. For example, a conference content pre-stored in an electronic device is projected in a conference, and activity rules and product information are projected in a large scale exhibition. In conventional technologies, a projection apparatus is integrated in a tablet computer to make it more convenient for a user to carry and use. In practice, if the height of projection needs to be adjusted, an additional things need to be put under the tablet computer to adjust the height of projection since the thickness of the body of the tablet computer is uniform.
Since the thickness of the body of the tablet computer in the conventional technologies is uniform and the height of the projection apparatus arranged on the tablet computer is constant, the projection height needs to be adjusted in other ways such as raising the tablet computer.
Further, there is no focusing button for projection in the tablet computer in the conventional technology. Therefore, the tablet computer is moved forward or backward when the focal length is required to be adjusted for the projector.
Besides, in the conventional technologies, the projection apparatus and the camera are two separate devices. In a conventional electronic device, a projection function of the projection apparatus and a camera function of the camera are simply added to obtain an integrated function.